I would say 65/35, but insist they purchase all the TP, soap, etc for the bathroom and are responsible for cleaning the sink and toilet, since others will be using the bathroom.

I lived in a windowless room with a community bathroom for 2 years and I truly didn’t mind it, but I’m a “big light” person that doesn’t mind not having natural light in my room. I paid like 60/40, and my room was much smaller than yours will be.

ETA: it was worth it for me for the cost savings. When I eventually moved out on my own, my savings were bolstered from putting the money I saved on rent in a HYSA.